⌖ Uranometria

EPHEMERIS

live looks and pass predictions of talkative birds

Real-time positions and pass predictions for the satellites you can actually talk to — amateur-radio birds and the ISS — propagated live with SGP4. Pointing is only as good as the elements' age, shown below.

Loading orbital elements…

Satellites—

Select a satellite

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Azimuth
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Elevation
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Range km
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Altitude km
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Sub-point
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Speed km/s
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Doppler
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Status

Sky view az / el

Ground track orbit ± one period

Sighting phone as theodolite

Hold this phone with its back to the sky and steer until the reticle on the sky view meets the bird — a pointing aid for a handheld yagi or your eyes. The compass alone is ±10°; align on the Sun or Moon — or on the bird itself during a pass — for degree-true hops. Between passes it aims you at the next rise point.

Next passes next 24 h · min 5° elevation

Select a satellite to predict passes.

Frequencies verify current status at AMSAT

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About accuracy

Positions come from publicly published orbital elements (TLEs) propagated with the standard SGP4 model. Fresh elements (under a few days old) give pointing good to a fraction of a degree; the TLE age readout warns you when they're getting stale. The sighting panel reads this phone's compass and gyro; a raw compass is only good to ~10°, so align on the Sun, the Moon, or on the bird itself — after alignment, pointing in the same part of the sky is good to a degree or two, plenty for a wide-beam yagi. This tracker is scoped to communicable satellites — amateur transponders and the ISS — not the full 19,000-object catalog, by design.